According to Current Theories of Planetary Formation, Why Is Saturn

According to current theories of planetary formation, why is Saturn less massive than Jupiter?

A) Saturn formed far out in the solar system where gas and dust were not as readily available as where Jupiter formed near the Sun.
B) Saturn formed in the inner part of the solar system where the rocky inner planets had already absorbed most of the material.
C) Saturn was originally more massive but has been repeatedly struck by large planetesimals that have stripped off some of its matter.
D) Jupiter formed first, using up or ejecting much of the material available in the outer solar system.